Tool

ABSTRACT

A cylindrical support for a cutting tool is provided with a plurality of grooves. A series of alternate sized cylindrical rollers are mounted in each groove and the cylindrical rollers are all in abutting relationship to each other. In addition, a helical cutting blade is mounted in each groove with one surface of the cutting blade bearing against a support wall of the groove and the other surface of the cutting blade facing and abutting the larger cylindrical rollers in each groove. The smaller cylindrical rollers in the grooves bear against the wall of the groove opposite to the wall that the cutting blade bears against. Each groove is provided with a threaded bore extending parallel to a longitudinal dimension of the groove. A set screw is threadedly mounted in each bore. The inner end of the set screw bears against the end cylindrical roller in each of the series of rollers. By screwing the set screw inwardly against the end roller the cylindrical rollers move relative to each other and transverse to the direction of the force exerted by the screw so that they move against the helical blade at spaced distances along the length of the blade forcing the helical blade against the supporting wall of the groove and locking the blade in the groove. This invention relates generally to a tool and more particularly to a mounting structure for helical carbide blades on a cutting tool.

United States Patent 1191 Sunderman et al.

1 1 TOOL [75] Inventors: Elwin Sunderman, lnglewood; Merle Hilliard, LosAngeles, both of Calif.

[73] Assignee: Sennet Tool and Manufacturing Company, Hawthorne, Calif.

[22] Filed: Dec. 7, i970 [21] Appl. No: 95,539

[52] US. Cl. 29/105 R, 29/96 R [51] Int. Cl ..B26d l/OO, 326d 1/12 [581Field of Search ..29/96, 97. 98, 105,

FORElGN PATENTS OR APPLlCATlONS Germany ..29/l()5 Great Britain .29/105Primary Examiner-Harrison L. Hinson Attorney-Julius 1,. Rubinstein 1 1Apr. 10, 1973 [5 7 1 ABSTRACT A cylindrical support for a cutting toolis provided with a plurality of grooves. A series of alternate sizedcylindrical rollers are mounted in each groove and the cylindricalrollers are all in abutting relationship to each other. In addition, ahelical cutting blade is mounted in each groove with one surface of thecutting blade bearing against a support wall of the groove and the othersurface of the Cutting blade facing and abutting the larger cylindricalrollers in each groove. The smaller cylindrical rollers in the groovesbear against the wall of the groove opposite to the wall that thecutting blade bears against. Each groove is provided with a threadedbore extending parallel to a longitudinal dimension of the groove. A setscrew is threadedly mounted in each bore. The inner end of the set screwbears against the end cylindrical roller in each of the series ofrollers. By screwing the set screw' inwardly against the end roller thecylindrical rollers move relative to each other and transverse to thedirection of the force exerted by the screw so that they move againstthe helical blade at spaced distances along the length of the bladeforcing the helical blade against the supporting wall of the groove andlocking the blade in the groove.

This invention relates generally to a tool and more particularly to amounting structure for helical carbide blades on a cutting tool.

20 Claims, 5 Drawing Figures PATENTEU APR 1 0 975 INVENTORS ME HILLIARDSUNDERMAN TOOL BACKGROUND AND BRIEF SUMMARY Helical end mills, shell endmills, and slab mills are frequently used with numerical controlledmilling machines. These helical cutting tools generally comprise helicalcarbide blades which are fastened to a cylindrical shank or support.After aperiod ofuse these blades wear and they must be readjusted tobring them back to their original size.

Heretofore, the helical carbide blades were brazed to the support bodyor shank, but brazing was objectionable because the heat required tobraze the blade to the support introduced stresses in the blade andthese stresses often caused unpredictable blade failure. Furthermore, itwas time consuming and difficult to heat the support bodies first toremove the blade for purposes of repair or replacement in order to bringthe tool back to its original size, and then to reheat the body again toagain braze the replaced or repaired blade to the support.

To overcome the problems caused by brazing the blade to the supportbody, other procedures were developed. A typical procedure involvedmounting the carbide blades in grooves formed in the support body andlocking the blades in the grooves by means of screw mounted wedges whichwere screwed into the grooves byradially mounted screws extendingthrough the screw holes in the wedges into the body of the shank orsupport.

This procedure required the surface of the wedge bearing against theface of the carbide blade to be machined to very close tolerances andthis necessary machining operation was expensive and time consuming.Furthermore, this arrangement also requires the surface of the carbideblade facing the wedge to be ground very smooth which further increasedthe cost of the carbide blade. This is because any imperfection in themachining of these surfaces would cause the wedge to bear against theside of the blade at points which could be spaced far enough apart tocause the carbide blade to crack. Besides this, the opposite surface ofthewedge also had to be ground smoothso it fit smoothly against theprecision finished side of the groove.

All these machine operations were very expensive. To overcome thedisadvantages inherent in the prior systems for locking the helicalbalde on a support, this invention includes grooves formed in thesupport body. A series of alternate sized cylindrical rollers arepositioned in each groove in an abutting relationship to each other.Helical carbide cutting blades are inserted in these grooves in such away that the largest of the cylindrical rollers in each series bearsagainst one surface of the blade. The opposite surface of the blade ineach groove bears against a support wall of the groove. With thisarrangement, if a force is directed against the end roller in the seriesof rollers, the remaining rollers in the series will move relative toeach other in a direction transverse to the direction of the force andin such a way that the larger rollers in each series moves against onesurface of the helical cutting blade at spaced points along the lengthof the blade. This forces the blade against the support wall of thegroove and locks the blade in the groove so long as force is directedagainst the end roller of the series of cylindrical rollers and istransmitted against the larger and/or smaller sets of rollers.Furthermore, the large number of points of engagement between thecylindrical rollers and the facing surface of the helical carbide lbladeresults in relatively small gaps between the rollers and this preventsthe blade from breaking. The free movement of the rollers permitspressure to be evenly spread along the length of the blade, thusaccommodating small. imperfections in the shape of the blade.Consequently, the facing surface of the carbide blade need not be groundto a high degree of precision.

Of course, blades mounted in cutting tools may have different shapes andit would be desirable to provide a blade locking mechanism which couldlock any blade having any shape or curvature on a support and to providesuch a mounting structure comprises an important object of thisinvention.

A further object of this invention is to provide a compact blademounting structure applied to a support thus permitting a greater numberof blades to be removably mounted on a given periphery of a support.

These and other objects of this invention will become more apparent whenunderstood in the light of the accompanying specification and drawings,wherein:

FIG. 1 is a perspective view of a cutting tool constructed according tothe principles of this invention.

FIG. 2 is a side elevational view of the cutting tool shown in'FIG. 1.

FIG. 3 is an end elevational view of the cutting tool.

FIG. 4 is an enlarged elevational view of a portion of the cylindricalsupport showing details of the locking mechanism.

' FIG. 5 is an elevational view of a portionof the blade lockingmechanism used with the cutting tool.

Referring now to FIG. 1 of the drawing, a cutting tool indicatedgenerally by the reference number 10 'includes a generally cylindricalmounting structure or support 12. In this particular embodiment thesupport includes a rear cylindrical stem 14 for insertion in a toolholder, and a forward portion 16 on which the blades are mounted. It is,however, to be understood that the shape of the support is not crucialto the practice of this invention and it is contemplated that thesupport for the cutting toolof this invention could have other shapes.For example, the support could be a cylindrical tube in shape, as on ashell end mill, or have any other suitable configuration. The forwardportion 16 includes a cutting end 20 and an inner end 22. In theparticular embodiment shown the blades project beyond the cutting end20, see FIG. 4, although this arrangement is not essential to thepractice of this invention, and it is contemplated that the blades couldbe mounted so they do not project beyond the ends of the support.

Generally axially extending blade receiving grooves 18 are formed on theperiphery of the forward portion 16. These grooves conform to thecontour of the blades which are to be locked in them and in the case ofa helical carbide blade, for example, the grooves would be helical. Ifthe blades to be locked in the supports were straight then the grooveswould have to be straight and so forth. In the particular embodimentshown eight blade receiving grooves are formed in the forward portion16.

As best seen in FIGS. 1 and 2,, the blade receiving grooves are formedintermediate the opposed ends 20 and 22 of the forward portion 16 of thesupport 12. These grooves are provided with partial end walls 24 and 26extending generally transverse to the length of the groove. An axiallyextending threaded screw receiving bore 28 is formed in end wall 24 andpressure screw 32 is mounted in this'bore. A threaded groove 30 isformed in end wall 26 and a screw 34 is mounted therein, see FIGS. 1,2and 4. End wall 24 extends part way across the width of the bladereceiving groove 18 defining thereby a blade receiving gap 25 at the endof the groove through which the cutting blade end 50 of the blade 44extends as it projects beyond the cutting end 20 of the support portion14. This permits the blade 44 to be shifted axially inthe groove bymeans of screw 34.

In this particular embodiment, the grooves are provided with a bladesupport wall 36 and this support wall conforms to the contour of thecutting blade to be mounted on the support. In this instance, helicalcarbide blades are to be mounted on the support so the support wallwould be helical, see FIG. 1.

A force or motion transmitting unit 38 is mounted in each groove. Theseunits comprise a first and second group of cylindrical rollers with therollers 40 in the first group twice the diameter of the rollers 42 inthe second group. The rollers in each motion transmitting unit arearranged in a series of alternate sizes in abutting relationship to eachother, as shown best in FIG. 4, and they are embedded in a slab ofrubber-like material 48. The slab is generally rectangular incrosssection and the rollers are arranged so the rollers of the largergroup are generally tangent to one surface of the slab while the rollersin the smaller group are generally tangent to the opposite surface ofthe slab, see FIG. 5. For the sake of clarity, the rubber slab 44 hasbeen removed in FIGS. 2 and 4 to illustrate the position of the rollersand the transmission of forces. The rubber slab in FIG. is partiallybroken away to show the position of the rollers in the slab.

In the present embodiment, helical carbide blades 44 are mounted in eachgroove with one surface abutting blade support wall 36 and the othersurface abutting the force transmitting unit in engagement with thelarger rollers 40, see FIG. 4.

When a helical carbide blade 44 is inserted in a blade receiving'groove18 along with the force or motion transmitting unit 38, as shown in FIG.4, then rotation of screw 32 inwardly and axially, see FIG. 4 causes theend of the screw 32 to engage the end roller in the series of rollersand this exerts lateral pressure on the force transmitting unit. Thispressure causes the rollers 40 and 42 to move relative to each other ina direction transverse to the direction of the force applied by screw 32and in such a way that the rollers 40 move into engagement with thefacing surface of the helical carbide blade opposite the surfaceengaging the blade support wall 36 while rollers 42 move in a generallyopposite direction contacting the inner wall of groove 18. In so doing,the regions of engagement between the cylindrical rollers 40 and thesurface of the helical carbide blade define a helical surface coincidentwith the surface 46 of the helical carbide blade. As shown in FIGS. 2and 4, the rollers 40 move into pressing and locking engagement with theblade 44 at uniformly spaced intervals along the length of the blade.This arrangement prevents blade fracture which occurred in prior bladelocking structures when the wedge was pressed against an irregularportion of the surface of the blade. With this arrangement, the helicalcontour of the blade fac ing the rollers 40 does not need to be groundso precisely because any irregularities in the contour are compensatedfor, by greater or lesser movements of the roller opposite the point ofirregularity.

As stated above, continuous use wears away the blade cutting edges. Whenthis occurs the blades may be easily removed by loosening screw 32 andremoving the blade 44 so that a shim can be inserted beneath the bladein groove 18. This causes the blade to be positioned outwardly from theaxis of the support so the blade can be locked on the support andreground 'to return to its proper size.

Cutting end 50 of blade 44 also becomes worn. When this happens theblade 40 may be readjusted by loosening screws 32 to loosen the blade44. Then the screws 34 may be screwed axially inwardly against the end52 of blade 44 to force the blade 44 longitudinally through gap adistance sufficient to permit the cutting end 50 to be reground toreturn to its proper size and shape.

Having described the invention, what I claim as new l. A cutting tool ofthe class described comprising a support, a plurality of generallyaxially extending blade receiving grooves formed on the periphery of thesupport, each support having one support wall shaped to conform to thecurvature of the blade to be mounted on the support, a motiontransmitting unit mounted in said groove, said motion transmitting unitincluding a plurality of spaced abutting members, said abutting membersmovable relative to each other at least in the direction of the width ofthe groove, a blade mounted in each groove, each blade mounted so onesurface bears against the support wall of the groove and the oppositesurface abuts said abutting members, and means for actuating said forcetransmitting unit so said abutting members are movable into lockingengagement with said opposite surface of the blade at spaced intervalsalong the length of the blade, the size of said abutting members andtheir numbers selected so the gaps between the point of engagementbetween the abutting members and said opposite surface of the blade aresmall enough to prevent the blade from cracking when the blade is lockedin the blade receiving groove.

2. A cutting tool of the class described comprising a support, saidsupport having a cutting end, a plurality of generally axially extendingblade receiving grooves formed on the periphery of the support, eachgroove having one support wall shaped to conform to the curvature of theblade to be mounted on the support and formed with end walls extendinggenerally transverse to the length of the groove, at least one end wallextending part way across the width of the groove and defining thereby ablade receiving gap at the cutting end of the support, a forcetransmitting unit in said groove, said force transmitting unit includinga plurality of spaced abutting members, said abutting members movablerelative to each other at least in the direction of the width of thegroove, a blade mounted in each groove and extendingthrough said gap,each blade mounted so one surface bears against the support wall of thegroove and the opposite surface abuts said abutting members, and meansfor actuating said force transmitting unit so said abutting members aremovable into locking engagement with said opposite surface of the bladeat spaced intervals along the length of the blade, the size of saidabutting members and their numbers selected so the space between thepoints of engagement between the abutting members and said oppositesurface of the blade are small enough to prevent the blade from crackingwhen the blade is locked in the blade receiving groove.

3, The cutting tool described in claim 1 wherein said means foractuating said force transmitting unit can be operated to permitmovement of said abutting members out of pressing engagement with saidblade to permit the blade to be removed from said support.

- 4. The cutting tool described in claim 2 wherein said means foractuating said force transmitting unit can be operated to permitmovement of said abutting members out of pressing engagement with saidblade to permit the blade to be removed from said support.

5. The cutting tool described in claim 2 including means mounted on saidsupport for moving each blade in a generally axially direction alongsaid groove for purposes of adjustment.

6. The cutting tool described in claim 2 wherein said end wall extendingpart way across each groove is provided with an axially extendingthreaded bore, a pressure screw in said bore, said pressure screwmovable against the force transmitting unit in said groove to exertpressure thereon to actuate said abutting members.

7. A cutting tool of the class described-comprising a support, aplurality of generally axially extending blade receiving grooves formedon the periphery of the support, each groove having one support wallshaped to conform to the curvature of the blades to be mounted in thegroove on the support, a force transmitting unit mounted in each groove,each force transmitting unit comprising a series of abutting rollersmounted in the groove and disposed along the length of the groove, thealternate rollers in each groove arranged so pressure exerted againstthe end of the series of rollers causes the rollers to move relative toeach other and in such a way that the rollers move transverse to thedirection of the force applying the pressure and transverse to thelength of the groove, a blade mounted in each groove, each blade mountedso one surface bears against the support wall of the groove and theopposite surface abuts said alternate rollers, and means on said supportfor exerting pressure against the end of each of the series of rollersto cause the alternate rollers to move into locking engagement with theopposite surface of the blade at spaced intervals along the length ofthe blade, the size of said abutting rollers and their numbers selectedso the space between the points of engagement between the abuttingmembers and said opposite surface of the blade are small enough toprevent the blade from cracking when the blade is locked in a bladereceiving groove.

8. A cutting tool of the class described comprising a support, aplurality of generally axially extending blade receiving grooves formedon the periphery of the support, each groove having one support wallshaped to conform to the curvature of the blades to be mounted in thegroove on the support, a force transmitting unit mounted in each groove,each force transmitting unit comprising a series of abutting rollersmounted in the groove and disposed along the length of the groove, thealternate rollers in each groove arranged so pressure exerted againstthe end of the series of rollers causes the rollers to move relative toeach other and in such a way that the rollers move transverse to thedirection of the force applying the pressure and transverse to thelength of the groove, a blade mounted in each groove, each blade mountedso one surface bears against the support wall of the groove and theopposite surface abuts said alternate rollers, andmeans on said supportfor exerting pressure against the end of each of the series of rollersto cause the alternate rollers to move into locking engagement with theopposite surface of the blade at spaced intervals along the length ofthe blade, and each series of rollers comprising alternate size rollers,said rollers arranged so the larger rollers constitute abutting membersand are movable into locking engagement with said opposite surface ofthe blade.

9. The cutting tool described in claim 8 wherein the alternate sizeseries of rollers comprising a first group of rollers and a second groupof rollers, the rollers in the first group twice the diameter of therollers in the second group, said rollers arranged so they are in aseries of alternate size.

10. A cutting tool of the class described comprising a support, saidsupport having a cutting end, a plurality of generally axially extendingblade receiving grooves formed on the periphery of the support, eachgroove having one support wall shaped to conform to the curvature of theblade to be mounted in the groove and formed with end walls extendinggenerally transverse to the length of the groove, at least one end wallextending part way across the width of the groove and defining thereby ablade receiving gap at the end of the groove so an end of the blade canproject beyond the cutting end of the support, a force transmitting unitin each groove, each force transmitting unit comprising a series ofabutting rollers mounted in the: groove anddisposed along the length ofthe groove, the alternate rollers in each groove arranged so pressureexerted against the end of the series of rollers causes the rollers tomove relative to each other in such a way that the rollers movetransverse to the direction of the force applying the pressure and movetransverse to the length of the groove, a blade mounted in each grooveand extending through said gap beyond the cutting end of the support,each blade mounted so one surface bears against the support wall of thegroove and the opposite surface abuts said alternate rollers, and meanson said support for exerting pressure against the end of each of theseries of rollers to cause the alternate rollers to move into lockingengagement with. the said opposite surface of the blade at spacedintervals along the length of the blade, the size of said rollers andtheir numbers selected so the spacing between the points of engagementbetween the rollers and said opposite surface of the blade is smallenough to prevent the blade from cracking when the blade is locked inthe blade receiving groove.

11. The cutting tool described in claim 10 wherein said end wallextending part way across the width of the groove is provided with anaxially extending threaded bore, a pressure screw in said bore, saidpressure screw movable against the end roller of the series of rollersin the adjacent groove to cause the alternate rollers to move intolocking engagement with the said opposite surface of the blade at spacedintervals along the length of the blade.

12. A cutting tool of the class described comprising a support, saidsupport having a cutting end, a plurality of generally axially extendingblade receiving grooves formed on the periphery of the support, eachgroove having one support wall shaped to conform to the curvature of theblade to be mounted in the groove and formed with end walls extendinggenerally transverse to the length of the groove, at least one end wallextending part way across the width of the groove and defining thereby ablade receiving gap at the end of the groove so an end of the blade canproject beyond the cutting end of the support, a force transmitting unitin each groove, each force transmitting unit comprising a series ofabutting rollers mounted in the groove and disposed along the length ofthe groove, the alternate rollers in each groove arranged so pressureexerted against the end of the series of rollers causes the rollers tomove relative to each other in such a way that the rollers movetransverse to the direction of the force applying the pressure and movetransverse to the length of the groove, a blade mounted in each grooveand extending through said gap beyond the cutting end of the support,each blade mounted so one surface bears against the support wall of thegroove and the opposite surface abuts said alternate rollers, and meanson said support for exerting pressure against the end of each of theseries of rollers to cause the alternate rollers to move into lockingengagement with the said opposite surface of the blade at spacedintervals along the length of the blade, said end wall extending partway across the width of the groove provided with an axially extendingthreaded bore, a pressure screw in said bore, said pressure screwmovable against the end roller of the series of rollers in the adjacentgroove-to cause the alternate rollers to move into locking engagementwith the said opposite surface of the blade at spaced intervals alongthe length of the blade, and each series of rollers comprise rollersarranged in alternate size, said rollers arranged so the larger rollersconstitute abutting members and are movable into locking engagement withsaid opposite surface of the blade.

13. The cutting tool described in claim 12 wherein the alternate sizeseries of rollers comprise a first group of rollers and a second groupof rollers, the rollers in the first group twice the diameter of therollers in the second group, said rollers arranged so they are in analternate size series.

14. The rollers described in claim 13 wherein said rollers are allcylindrical.

15. The cutting tool described in claim 10 including means mounted onsaid support for moving each blade in a generally axial direction alongsaid groove through said blade receiving gap for purposes of adjustment.

16. The cutting tool described in claim 15 wherein said means for movingsaid blade in an axial direction comprises a screw receiving threadedgroove formedin the end wall of each groove opposite said one end wall,

a screw threaded in each groove, each screw movable into engagement withan end of each blade so that by rotating said screw said blades can bemoved axially in said grooves through said blade receiving gap in thedirection of the cutting end of said support.

17. A cutting tool of the class described comprising a support, aplurality of grooves formed in said support, a blade and a forcetransmitting unit mounted in each groove, each force transmitting unitcomprising a series of rollers embedded in a rubber-like material, saidrollers arranged so pressure against the side of each unit causes someof the rollers to move relative to each other in a direction transverseto the direction of the force applying the pressure and against asurface of the blade to releasably lock the blade in the groove, andmeans on the support for exerting pressure against the side of eachforce transmitting unit.

18. The cutting tool described in claim 17 wherein the rollers in saidseries of rollers are alternate size and are embedded in a slab ofrubber-like material generally rectangular in cross-section, saidrollers arranged so the larger rollers are generally tangent to onesurface of the slab and the smaller rollers are generally tangent to theopposite surface of the slab, the larger rollers disposed against asurface of the blade and movable into engagement therewith to releasablylock the blade into the groove.

19. The cutting tool described in claim 18 wherein the larger rollersare twice the diameter of the smaller rollers.

20. The cutting tool described in claim 19 wherein the rollers arecylindrical.

1. A cutting tool of the class described comprising a support, aplurality of generally axially extending blade receiving grooves formedon the periphery of the support, each support having one support wallshaped to conform to the curvature of the blade to be mounted on thesupport, a motion transmitting unit mounted in said groove, said motiontransmitting unit including a plurality of spaced abutting members, saidabutting members movable relative to each other at least in thedirection of the width of the groove, a blade mounted in each groove,each blade mounted so one surface bears against the support wall of thegroove and the opposite surface abuts said abutting members, and meansfor actuating said force transmitting unit so said abutting members aremovable into locking engagement with said opposite surface of the bladeat spaced intervals along the length of the blade, the size of saidabutting members and their numbers selected so the gaps between thepoint of engagement between the abutting members and said oppositesurface of the blade are small enough to prevent the blade from crackingwhen the blade is locked in the blade receiving groove.
 2. A cuttingtool of the class described comprising a support, said support having acutting end, a plurality of generally axially extending blade receivinggrooves formed on the periphery of the support, each groove having onesupport wall shaped to conform to the curvature of the blade to bemounted on the support and formed with end walls extending generallytransverse to the length of the groove, at least one end wall extendingpart way across the width of the groove and defining thereby a bladereceiving gap at the cutting end of the support, a force transmittingunit in said groove, said force transmitting unit including a pluralityof spaced abutting members, said abutting members movable relative toeach other at least in the direction of the width of the groove, a blademounted in each groove and extending through said gap, each blademounted so one surface bears against the support wall of the groove andthe opposite surface abuts said abutting members, and means foractuating said force transmitting unit so said abutting members aremovable into locking engagement with said opposite surface of the bladeat spaced intervals along the length of the blade, the size of saidabutting members and their numbers selected so the space between thepoints of engagement between the abutting members and said oppositesurface of the blade are small enough to prevent the blade from crackingwhen the blade is locked in the blade receiving groove.
 3. The cuttingtool descriBed in claim 1 wherein said means for actuating said forcetransmitting unit can be operated to permit movement of said abuttingmembers out of pressing engagement with said blade to permit the bladeto be removed from said support.
 4. The cutting tool described in claim2 wherein said means for actuating said force transmitting unit can beoperated to permit movement of said abutting members out of pressingengagement with said blade to permit the blade to be removed from saidsupport.
 5. The cutting tool described in claim 2 including meansmounted on said support for moving each blade in a generally axiallydirection along said groove for purposes of adjustment.
 6. The cuttingtool described in claim 2 wherein said end wall extending part wayacross each groove is provided with an axially extending threaded bore,a pressure screw in said bore, said pressure screw movable against theforce transmitting unit in said groove to exert pressure thereon toactuate said abutting members.
 7. A cutting tool of the class describedcomprising a support, a plurality of generally axially extending bladereceiving grooves formed on the periphery of the support, each groovehaving one support wall shaped to conform to the curvature of the bladesto be mounted in the groove on the support, a force transmitting unitmounted in each groove, each force transmitting unit comprising a seriesof abutting rollers mounted in the groove and disposed along the lengthof the groove, the alternate rollers in each groove arranged so pressureexerted against the end of the series of rollers causes the rollers tomove relative to each other and in such a way that the rollers movetransverse to the direction of the force applying the pressure andtransverse to the length of the groove, a blade mounted in each groove,each blade mounted so one surface bears against the support wall of thegroove and the opposite surface abuts said alternate rollers, and meanson said support for exerting pressure against the end of each of theseries of rollers to cause the alternate rollers to move into lockingengagement with the opposite surface of the blade at spaced intervalsalong the length of the blade, the size of said abutting rollers andtheir numbers selected so the space between the points of engagementbetween the abutting members and said opposite surface of the blade aresmall enough to prevent the blade from cracking when the blade is lockedin a blade receiving groove.
 8. A cutting tool of the class describedcomprising a support, a plurality of generally axially extending bladereceiving grooves formed on the periphery of the support, each groovehaving one support wall shaped to conform to the curvature of the bladesto be mounted in the groove on the support, a force transmitting unitmounted in each groove, each force transmitting unit comprising a seriesof abutting rollers mounted in the groove and disposed along the lengthof the groove, the alternate rollers in each groove arranged so pressureexerted against the end of the series of rollers causes the rollers tomove relative to each other and in such a way that the rollers movetransverse to the direction of the force applying the pressure andtransverse to the length of the groove, a blade mounted in each groove,each blade mounted so one surface bears against the support wall of thegroove and the opposite surface abuts said alternate rollers, and meanson said support for exerting pressure against the end of each of theseries of rollers to cause the alternate rollers to move into lockingengagement with the opposite surface of the blade at spaced intervalsalong the length of the blade, and each series of rollers comprisingalternate size rollers, said rollers arranged so the larger rollersconstitute abutting members and are movable into locking engagement withsaid opposite surface of the blade.
 9. The cutting tool described inclaim 8 wherein the alternate size series of rollers comprising a firstgroup of rollerS and a second group of rollers, the rollers in the firstgroup twice the diameter of the rollers in the second group, saidrollers arranged so they are in a series of alternate size.
 10. Acutting tool of the class described comprising a support, said supporthaving a cutting end, a plurality of generally axially extending bladereceiving grooves formed on the periphery of the support, each groovehaving one support wall shaped to conform to the curvature of the bladeto be mounted in the groove and formed with end walls extendinggenerally transverse to the length of the groove, at least one end wallextending part way across the width of the groove and defining thereby ablade receiving gap at the end of the groove so an end of the blade canproject beyond the cutting end of the support, a force transmitting unitin each groove, each force transmitting unit comprising a series ofabutting rollers mounted in the groove and disposed along the length ofthe groove, the alternate rollers in each groove arranged so pressureexerted against the end of the series of rollers causes the rollers tomove relative to each other in such a way that the rollers movetransverse to the direction of the force applying the pressure and movetransverse to the length of the groove, a blade mounted in each grooveand extending through said gap beyond the cutting end of the support,each blade mounted so one surface bears against the support wall of thegroove and the opposite surface abuts said alternate rollers, and meanson said support for exerting pressure against the end of each of theseries of rollers to cause the alternate rollers to move into lockingengagement with the said opposite surface of the blade at spacedintervals along the length of the blade, the size of said rollers andtheir numbers selected so the spacing between the points of engagementbetween the rollers and said opposite surface of the blade is smallenough to prevent the blade from cracking when the blade is locked inthe blade receiving groove.
 11. The cutting tool described in claim 10wherein said end wall extending part way across the width of the grooveis provided with an axially extending threaded bore, a pressure screw insaid bore, said pressure screw movable against the end roller of theseries of rollers in the adjacent groove to cause the alternate rollersto move into locking engagement with the said opposite surface of theblade at spaced intervals along the length of the blade.
 12. A cuttingtool of the class described comprising a support, said support having acutting end, a plurality of generally axially extending blade receivinggrooves formed on the periphery of the support, each groove having onesupport wall shaped to conform to the curvature of the blade to bemounted in the groove and formed with end walls extending generallytransverse to the length of the groove, at least one end wall extendingpart way across the width of the groove and defining thereby a bladereceiving gap at the end of the groove so an end of the blade canproject beyond the cutting end of the support, a force transmitting unitin each groove, each force transmitting unit comprising a series ofabutting rollers mounted in the groove and disposed along the length ofthe groove, the alternate rollers in each groove arranged so pressureexerted against the end of the series of rollers causes the rollers tomove relative to each other in such a way that the rollers movetransverse to the direction of the force applying the pressure and movetransverse to the length of the groove, a blade mounted in each grooveand extending through said gap beyond the cutting end of the support,each blade mounted so one surface bears against the support wall of thegroove and the opposite surface abuts said alternate rollers, and meanson said support for exerting pressure against the end of each of theseries of rollers to cause the alternate rollers to move into lockingengagement with the said opposite surface of the blade at Spacedintervals along the length of the blade, said end wall extending partway across the width of the groove provided with an axially extendingthreaded bore, a pressure screw in said bore, said pressure screwmovable against the end roller of the series of rollers in the adjacentgroove to cause the alternate rollers to move into locking engagementwith the said opposite surface of the blade at spaced intervals alongthe length of the blade, and each series of rollers comprise rollersarranged in alternate size, said rollers arranged so the larger rollersconstitute abutting members and are movable into locking engagement withsaid opposite surface of the blade.
 13. The cutting tool described inclaim 12 wherein the alternate size series of rollers comprise a firstgroup of rollers and a second group of rollers, the rollers in the firstgroup twice the diameter of the rollers in the second group, saidrollers arranged so they are in an alternate size series.
 14. Therollers described in claim 13 wherein said rollers are all cylindrical.15. The cutting tool described in claim 10 including means mounted onsaid support for moving each blade in a generally axial direction alongsaid groove through said blade receiving gap for purposes of adjustment.16. The cutting tool described in claim 15 wherein said means for movingsaid blade in an axial direction comprises a screw receiving threadedgroove formed in the end wall of each groove opposite said one end wall,a screw threaded in each groove, each screw movable into engagement withan end of each blade so that by rotating said screw said blades can bemoved axially in said grooves through said blade receiving gap in thedirection of the cutting end of said support.
 17. A cutting tool of theclass described comprising a support, a plurality of grooves formed insaid support, a blade and a force transmitting unit mounted in eachgroove, each force transmitting unit comprising a series of rollersembedded in a rubber-like material, said rollers arranged so pressureagainst the side of each unit causes some of the rollers to moverelative to each other in a direction transverse to the direction of theforce applying the pressure and against a surface of the blade toreleasably lock the blade in the groove, and means on the support forexerting pressure against the side of each force transmitting unit. 18.The cutting tool described in claim 17 wherein the rollers in saidseries of rollers are alternate size and are embedded in a slab ofrubber-like material generally rectangular in cross-section, saidrollers arranged so the larger rollers are generally tangent to onesurface of the slab and the smaller rollers are generally tangent to theopposite surface of the slab, the larger rollers disposed against asurface of the blade and movable into engagement therewith to releasablylock the blade into the groove.
 19. The cutting tool described in claim18 wherein the larger rollers are twice the diameter of the smallerrollers.
 20. The cutting tool described in claim 19 wherein the rollersare cylindrical.